Load data from serialization to listbox - vb.net

Question

I am able to write to the file perfectly... however I am having trouble reading from file and inserting read data into a listbox.
Public myData As New MySettings
Public saveFile As String = ("mysettings.ini")
'SAVE INFO TO SETTINGS FILE
Dim fs As Stream = New FileStream(saveFile, FileMode.Create)
Dim bf As BinaryFormatter = New BinaryFormatter()
For l_index As Integer = 0 To ListBox1.Items.Count - 1
Dim l_text As String = CStr(ListBox1.Items(l_index))
bf.Serialize(fs, l_text)
Next
fs.Close()
Return
This is the part where I am having trouble...
'LOAD INFO FROM SETTINGS FILE
Dim fs As Stream = New FileStream(saveFile, FileMode.Open)
Dim bf As BinaryFormatter = New BinaryFormatter()
For l_index As Integer = 0 To saveFile.Count - 1
Dim l_text As String = CStr(saveFile(l_index))
'myData = CType(bf.Deserialize(fs), CType(myData))
ListBox1.Items.Add(myData)
Next
fs.Close()
Return
Any help at all would be appreciated, even a point in the right direction.
Thanks in advance!!

Answer 1

The ListBox ObjectCollection (Items) is not marked as serializable, so you cant serialize the entire thing at once. You may have encountered this and used the loop to serialize each item. The loop does appear to serialize each item, but I don't know how you can deserialize in a loop - you wont know how many items there are, nor will the Serializer.
Rather than one item at a time, you could copy the ListBox items to an array and serialize the entire thing:
Dim ary(lb.Items.Count - 1) As Object
lb.Items.CopyTo(ary, 0)
' OpenOrCreate!
Using fs As New FileStream("C:\Temp\lbitems.bin", FileMode.OpenOrCreate)
Dim bf As New BinaryFormatter
bf.Serialize(fs, ary)
End Using ' close and dispose of stream
Deserialization is just the reverse:
Using fs As New FileStream("C:\Temp\lbitems.bin", FileMode.Open)
Dim bf As New BinaryFormatter
Dim myAry = bf.Deserialize(fs)
lb.Items.Clear()
lb.Items.Add(myAry)
End Using
You can make it a bit simpler using a List(of String) and assign it as the DataSource.
Private myLBItems As New List(Of String)
...
' fake items to add
myLBItems.Add("Foo")
myLBItems.Add("Bar")
myLBItems.Add("Option")
myLBItems.Add("Strict")
lb.DataSource = myLBItems
Using the List as the DataSource, you dont have to copy items from here to there - whatever is in the List will appear in the ListBox. Serialization is simple too:
bf.Serialize(fs, myLBItems)
Since Deserializing returns an Object, you need to cast it (Option Strict):
myLBItems = CType(bf.Deserialize(fs), List(Of String))
Note: This may not be doing what you want at all. Your code is serializing what is in the ListBox after converting it to String. Later, it looks like you want to Deserialize to a MySettings Type.
If MySettings is something like a Name and Value pair (or collection of them), probably half the data and all the Type information will have been lost.